The present invention relates to a power-driven hand-held tool, in which a tool-receiving spindle is rotated by means of a pneumatic motor.
Known hand-held tools of the type under consideration are basically divided into two groups. In one of these groups a specifically high output with a little air consumption is achieved by small manufacture allowances of metal component parts of the pneumatic motor and also by the axial rigging of the components of the pneumatic motor in the housing of the tool for a precisely defined positioning. Such a construction involves high expenses and makes an oscillation-isolated suspension of the pneumatic motor in the tool housing difficult.
In the hand-held tools of another group costly cast iron or plastics component parts are partially combined with simple steel elements. Because of required large plays and tolerances and non-optimal air stream ratio, these motors have a non-satisfactory efficiency and therefore a high pressure air consumption.
The manufacture of such tools has been, however, expensive though an oscillation-isolated suspension of the motor in the tool housing could be easily obtained in the assembled tool.